Ever since letters contaminated with weapons-grade Bacillus anthracis (anthrax) spores passed through the United States Postal Service (USPS) in the fall of 2001 and the “letter bombs” mailed in the 1980s, there has been a heightened awareness that chemical, biological, radiological or explosive threats could be hidden in an item of mail. Thus, there is an ongoing need to develop new technologies to address such potential threats. Due to the volume of mail that must be screened, it is desirable that any such screening technology be cost effective.
The USPS is not the only organization that delivers mail and parcels. Commercial shippers and the U.S. military also manage the shipment and delivery of large volumes of parcels. It would be desirable to provide a screening technology that is sensitive and cost effective. Such a technology will preferably be capable of screening for chemical, biological, radiological, nuclear or explosive (CBRNE) threats. Similarly, such a technology would be useful for screening luggage and cargo prior to transportation.